Multiple Vulnerabilities in PHP Could Allow for Arbitrary Code Execution

MS-ISAC ADVISORY NUMBER:

2017-014

DATE(S) ISSUED:

02/21/2017

OVERVIEW:

Multiple vulnerabilities have been discovered in PHP, the most severe of which could allow an attacker to execute arbitrary code. PHP is a programming language originally designed for use in web-based applications with HTML content. PHP supports a wide variety of platforms and is used by numerous web-based software applications. Successfully exploiting the most severe of these vulnerabilities could allow for remote attackers to execute arbitrary code in the context of the affected application. Failed exploitation could result in a denial-of-service condition.

THREAT INTELLIGENCE:

There are currently no reports of these vulnerabilities being exploited in the wild. There is known proof-of-concept code for these vulnerabilities.

SYSTEMS AFFECTED:

PHP 7.0 prior to 7.0.16

PHP 7.1 prior to 7.1.2

RISK:

Government:

Large and medium government entities: HIGH

Small government entities: HIGH

Businesses:

Large and medium business entities: HIGH

Small business entities: HIGH

Home Users:

LOW

TECHNICAL SUMMARY:

PHP has released updates that address multiple vulnerabilities, the most severe of which could allow for arbitrary code execution. These vulnerabilities include:

Successfully exploiting the most severe of these vulnerabilities could allow for remote attackers to execute arbitrary code in the context of the affected application. Failed exploitation could result in a denial-of-service condition.

RECOMENDATIONS:

We recommend the following actions be taken:

·Upgrade to the latest version of PHP immediately, after appropriate testing.

·Verify no unauthorized system modifications have occurred on system before applying patch.

·Apply the principle of Least Privilege to all systems and services.

·Remind users not to visit websites or follow links provided by unknown or untrusted sources.